Stacks of internally connected surface-mediated cells and methods of operating same

• US 20130162216A1
• Filed: 12/21/2011
• Published: 06/27/2013
• Est. Priority Date: 12/21/2011
• Status: Active Grant

• Current Assignee: Honeycomb Battery Co. (Global Graphene Group, Inc.)
• Original Assignee: Chen Guorong
• Inventors: Zhamu, Aruna, Wang, Xiqing, Jang, Bor Z., Chen, GuoRong, Wang, Yanbo
• Granted Patent: US 9,349,542 B2
• Time in Patent Office: Days
• US Class Current: 320/130
• CPC Class Codes: H01G 11/06 with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC]
• CPC Class Codes: H01G 11/10 Multiple hybrid or EDL capacitors, e.g. arrays or modules housings, cases, encapsulations or mountings thereof H01G11/78
• CPC Class Codes: H01G 11/32 Carbon-based
• CPC Class Codes: H01G 11/72 specially adapted for integration in multiple or stacked hybrid or EDL capacitors
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 4/133 Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/583 Carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

An energy storage stack of at least two surface-mediated cells (SMCs) internally connected in parallel or in series. The stack includes: (A) At least two SMC cells, each consisting of (i) a cathode comprising a porous cathode current collector and a cathode active material; (ii) a porous anode current collector; and (iii) a porous separator disposed between the cathode and the anode; (B) A lithium-containing electrolyte in physical contact with all the electrodes, wherein the cathode active material has a specific surface area no less than 100 m²/g in direct physical contact with the electrolyte to receive lithium ions therefrom or to provide lithium ions thereto; and (C) A lithium source. This new-generation energy storage device exhibits the highest power densities of all energy storage devices, much higher than those of all the lithium ion batteries, lithium ion capacitors, and supercapacitors.

Claims

1. An energy storage stack of at least two surface-mediated cells (SMCs) internally connected, said stack comprising:

(A) a first SMC consisting of;

a. A first cathode comprising a first cathode current collector and a first cathode active material coated on at least one surface of the first cathode current collector, wherein said cathode active material has a surface area to capture or store lithium thereon;

b. A first anode being formed of a first anode current collector having a surface area to capture or store lithium thereon;

c. A first porous separator disposed between the first cathode and the first anode;

(B) a second SMC consisting of;

a. A second cathode comprising a second cathode current collector and a second cathode active material coated on at least one surface of the second cathode current collector, wherein said second cathode active material has a surface area to capture or store lithium thereon;

b. A second anode being formed of a second anode current collector having a surface area to capture or store lithium thereon;

c. A second porous separator disposed between the second cathode and the second anode;

(C) a lithium-containing electrolyte in physical contact with a cathode and an anode in each SMC; and

(D) at least a lithium source implemented at or near at least one of the anodes or cathodes prior to a first charge or a first discharge cycle of the energy storage stack;

wherein said first or second cathode active material has a specific surface area of no less than 100 m²/g being in direct physical contact with said electrolyte to receive lithium ions therefrom or to provide lithium ions thereto.

2. The energy storage stack of claim 1 containing at least the first and the second SMCs that are internally connected in parallel, wherein at least one of the cathode current collectors and at least one of the anode current collectors are porous and the electrolyte in the first SMC is in fluid communication with the electrolyte in the second SMC.

3. The energy storage stack of claim 1 containing at least the first and the second SMCs that are internally connected in series, wherein said stack contains at least a bipolar electrode made of a non-porous but electronically conducting solid layer having one surface optionally coated with an anode active material and an opposing surface coated with a cathode active material, and the electrolyte in the first SMC is not in fluid communication with the electrolyte in the second SMC.

4. The energy storage stack of claim 1, wherein at least one of said first anode and said second anode further contains an anode active material having a specific surface area of no less than 100 m²/g which is in direct physical contact with said electrolyte to receive lithium ions therefrom or to provide lithium ions thereto.

5. The energy storage stack of claim 1, wherein at least one of said first anode and second anode further contains an anode active material having a specific surface area of no less than 500 m²/g which is in direct physical contact with said electrolyte to receive lithium ions therefrom or to provide lithium ions thereto.

6. The energy storage stack of claim 2, wherein said first anode current collector and said second anode current collector are connected to an anode terminal, and said first cathode current collector and said second cathode current collector are connected to a cathode terminal.

7. The energy storage stack of claim 2, wherein at least one of the anode current collectors or cathode current collectors is a porous, electrically conductive material selected from metal foam, metal web or screen, perforated metal sheet, metal fiber mat, metal nanowire mat, porous conductive polymer film, conductive polymer nano-fiber mat or paper, conductive polymer foam, carbon foam, carbon aerogel, carbon xerox gel, graphene foam, graphene oxide foam, reduced graphene oxide foam, carbon fiber paper, graphene paper, graphene oxide paper, reduced graphene oxide paper, carbon nano-fiber paper, carbon nano-tube paper, or a combination thereof.

8. The energy storage stack of claim 1, wherein the lithium source comprises a lithium chip, lithium foil, lithium powder, surface stabilized lithium particles, lithium film coated on a surface of an anode or cathode current collector, lithium film coated on a surface of a cathode active material, or a combination thereof.

9. The energy storage stack of claim 4, wherein the lithium source comprises a lithium chip, lithium foil, lithium powder, surface-stabilized lithium particles, lithium film coated on a surface of an anode or cathode current collector, lithium film coated on a surface of an anode or cathode active material, or a combination thereof.

10. The energy storage stack of claim 1, wherein at least one of said anode current collectors or at least one of the cathode active materials is pre-loaded with lithium before or when the stack is made.

11. The energy storage stack of claim 4 wherein at least one of the anode and cathode active materials forms a porous anode structure and is selected from:

(a) A porous disordered carbon material selected from a soft carbon, hard carbon, polymeric carbon or carbonized resin, meso-phase carbon, coke, carbonized pitch, carbon black, activated carbon, or partially graphitized carbon;

(b) A graphene material selected from a sheet or multiple sheets of single-layer graphene, multi-layer graphene, graphene oxide, graphene fluoride, hydrogenated graphene, nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, chemically reduced graphene oxide, or thermally reduced graphene oxide;

(c) Exfoliated graphite;

(d) Meso-porous carbon;

(e) A carbon nanotube selected from a single-walled carbon nanotube or multi-walled carbon nanotube;

(f) A carbon nano-fiber, metal nano-wire, metal oxide nano-wire or fiber, or conductive polymer nano-fiber, or

(g) A combination thereof.

12. The energy storage stack of claim 1 wherein at least one of said cathode active materials forms a porous structure and is selected from:

(a) A porous disordered carbon material selected from a soft carbon, hard carbon, polymeric carbon or carbonized resin, meso-phase carbon, coke, carbonized pitch, carbon black, activated carbon, or partially graphitized carbon;

(b) A graphene material selected from a single-layer graphene, multi-layer graphene, graphene oxide, graphene fluoride, hydrogenated graphene, nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, functionalized graphene, or reduced graphene oxide;

(c) Exfoliated graphite;

(d) Meso-porous carbon;

(e) A carbon nanotube selected from a single-walled carbon nanotube or multi-walled carbon nanotube;

(f) A carbon nano-fiber, metal nano-wire, metal oxide nano-wire or fiber, or conductive polymer nano-fiber, or

(g) A combination thereof.

13. The energy storage stack of claim 1 wherein at least one of said cathode active materials is a functionalized graphene material having a lithium-capturing functional group, said graphene material being selected from a single-layer sheet or multi-layer platelet of pristine graphene, graphene fluoride, hydrogenated graphene, nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, or chemically or thermal reduced graphene oxide.

14. The energy storage stack of claim 4 wherein at least one of said anode and cathode active materials is a single-walled or multi-walled carbon nanotube (CNT), oxidized CNT, fluorinated CNT, hydrogenated CNT, nitrogenated CNT, boron-doped CNT, nitrogen-doped CNT, or doped CNT.

15. The energy storage stack of claim 2, wherein said stack has an open-circuit voltage of at least 1.5 volts and said stack is operated at a voltage no less than 1.5 volts after a first cycle.

16. The energy storage stack of claim 2, wherein said stack operates in a voltage range of from 1.0 volts to 4.5 volts.

17. The energy storage stack of claim 3, wherein said stack operates in a voltage range between 1.0·

n volts and 4.5·

n volts, where n is an integer greater than 1 and less than 1,000.

18. The energy storage stack of claim 3, wherein said stack operates in a voltage range between 1.5·

n volts and 4.0·

n volts, where n is an integer greater than 1 and less than 1,000.

19. The energy storage stack of claim 3, wherein at least 90% of the lithium is stored on surfaces of said anode active material when the device is in a charged state, or at least 90% of the lithium is stored on surfaces of said first and second cathode active materials when the device is in a discharged state.

20. The energy storage stack of claim 1, wherein a charge or discharge operation of said stack does not involve lithium intercalation or solid state diffusion.

21. The energy storage stack of claim 1, wherein the electrolyte is liquid electrolyte or gel electrolyte containing a first amount of lithium ions dissolved therein.

22. The energy storage stack of claim 21, wherein an operation of said stack involves an exchange of a second amount of lithium ions between said cathodes and said anodes, and said second amount of lithium is greater than said first amount.

23. The energy storage stack of claim 1, wherein at least one of the cathode active materials or one of the anode current collectors has a specific surface area of no less than 500 m²/g that is in direct contact with said electrolyte.

24. The energy storage stack of claim 1, wherein at least one of the cathode active materials or one of the anode current collectors has a specific surface area of no less than 1,500 m²/g that is in direct contact with said electrolyte.

25. The energy storage stack of claim 4, wherein at least 80% of the lithium is stored on surfaces of said anode active materials when the stack is in a charged state, or at least 80% of the lithium is stored on surfaces of said cathode active materials when the stack is in a discharged state.

26. The energy storage stack of claim 1, wherein an electric double layer mechanism contributes to less than 10% of the charge storage capacity of said device.

27. The energy storage stack of claim 1, wherein at least one of the cathode active materials has a surface area that does not contain a functional group thereon, and said functional group-free surface is exposed to said electrolyte.

28. The energy storage stack of claim 1 wherein said lithium source is selected from lithium metal, a lithium metal alloy, a mixture of lithium metal or lithium alloy with a lithium intercalation compound, a lithiated compound, lithiated titanium dioxide, lithium titanate, lithium manganate, a lithium transition metal oxide, Li₄Ti₅O₁₂, or a combination thereof.

29. The energy storage device of claim 28, wherein the lithium intercalation compound or lithiated compound is selected from the following groups of materials:

(a) Lithiated silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), cobalt (Co), nickel (Ni), manganese (Mn), cadmium (Cd), and mixtures thereof;

(b) Lithiated alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Co, Ni, Mn, Cd, and their mixtures;

(c) Lithiated oxides, carbides, nitrides, sulfides, phosphides, selenides, tellurides, or antimonides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, Ni, Mn, Cd, and mixtures or composites thereof, and

(d) Lithiated salts or hydroxides of Sn.

30. The energy storage stack of claim 29 wherein the lithium intercalation compound or lithiated compound is a nano-structured material having at least a dimension less than 100 nm.

31. The energy storage stack of claim 29 wherein the lithium intercalation compound or lithiated compound is a nano-structured material having at least a dimension less than 20 nm.

32. The energy storage stack of claim 28 wherein the lithium source is a nano-structured material having at least a dimension less than 100 nm.

33. The energy storage stack of claim 28 wherein the lithium source is a nano-structured material having at least a dimension less than 20 nm.

34. The energy storage stack of claim 1 wherein said electrolyte comprises a lithium salt-doped ionic liquid, a liquid organic solvent, or a gel electrolyte.

35. The energy storage stack of claim 1 wherein said stack device provides an energy density of no less than 200 Wh/kg and power density no lower than 30 Kw/kg, all based on a single electrode weight.

36. The energy storage stack of claim 1 wherein said device provides an energy density of no less than 400 Wh/kg or power density no less than 50 Kw/kg, all based on a single electrode weight.

37. The energy storage stack of claim 1 wherein said device provides an energy density of no less than 600 Wh/kg or a power density no less than 100 Kw/kg, all based on a single electrode weight.

38. The energy storage stack of claim 1 wherein at least one of said positive electrodes has a thickness greater than 50 μ

m.

39. A method of operating the energy storage stack of claim 1, said method including implementing a lithium source at or near (a) at least one of the anodes, and ionizing said lithium source to release lithium ions into said electrolyte during the first discharge cycle of said stack;

or (b) near or at least one of the cathodes, and operating said lithium source to release lithium ions into said electrolyte during the first charge cycle of said stack.

40. A method of operating the energy storage stack of claim 2, said method including implementing a lithium source at said first anode, ionizing said lithium source to release lithium ions into said electrolyte during a first discharge cycle of said stack, and electrochemically driving said released lithium ions to all of said cathodes where said released lithium ions are captured by cathode active material surfaces.

41. The method of claim 40, further comprising a step of releasing lithium ions from said cathode surfaces during a re-charge cycle of said stack, electrically driving said released lithium ions to anode surfaces using an external battery charging device.

42. The method of claim 39, wherein a charge and a discharge of said stack do not involve lithium intercalation or solid state diffusion.

43. A method of operating a stack of surface-mediated cells, said method including:

(A) Providing a stack of at least two surface-mediated cells internally connected, wherein each cell comprising an anode composed an anode current collector and an anode active material having a specific surface area greater than 100 m²/g and being coated on at least a surface of said anode current collector, a cathode composed of a porous cathode current collector and a cathode active material having a specific surface area greater than 100 m²/g and being coated on at least one surface of said cathode current collector, a porous separator separating said anode and said cathode, liquid or gel electrolyte having an initial amount of lithium ions dissolved therein and being in ionic contact with each anode and cathode, and at least a lithium source in physical contact with said electrolyte;

(B) Releasing lithium ions from said lithium source into said electrolyte during the first discharge of said stack, capturing lithium ions from said electrolyte and storing said captured lithium on cathode surfaces; and

(C) Exchanging an amount of lithium ions, greater than said initial amount, between anode active material surfaces and cathode active material surfaces during a subsequent charge or discharge operation, wherein said operation involves no lithium intercalation.

44. The method of claim 43, wherein at least a cathode and an anode each has a specific surface area greater than 500 m²/g.